transform8x8.c

压缩JM12.3d的完整的全部C语言的代码文档,用于嵌入式系统的压缩编解码

    mpr[jpos5][ipos7] = (imgpel) ((P_D + P_F + 2*P_E + 2) >> 2);
    mpr[jpos1][ipos6] =
    mpr[jpos3][ipos7] = (imgpel) ((P_E + P_G + 2*P_F + 2) >> 2);
    mpr[jpos1][ipos7] = (imgpel) ((P_F + P_H + 2*P_G + 2) >> 2);
    mpr[jpos2][ipos0] =
    mpr[jpos4][ipos1] =
    mpr[jpos6][ipos2] = (imgpel) ((P_R + P_Z + 2*P_Q + 2) >> 2);
    mpr[jpos3][ipos0] =
    mpr[jpos5][ipos1] =
    mpr[jpos7][ipos2] = (imgpel) ((P_S + P_Q + 2*P_R + 2) >> 2);
    mpr[jpos4][ipos0] =
    mpr[jpos6][ipos1] = (imgpel) ((P_T + P_R + 2*P_S + 2) >> 2);
    mpr[jpos5][ipos0] =
    mpr[jpos7][ipos1] = (imgpel) ((P_U + P_S + 2*P_T + 2) >> 2);
    mpr[jpos6][ipos0] = (imgpel) ((P_V + P_T + 2*P_U + 2) >> 2);
    mpr[jpos7][ipos0] = (imgpel) ((P_W + P_U + 2*P_V + 2) >> 2);
    break;

  case  HOR_DOWN_PRED:/* diagonal prediction -22.5 deg to horizontal plane */
    if ((!block_available_up)||(!block_available_left)||(!block_available_up_left))
      printf ("warning: Intra_8x8_Horizontal_Down prediction mode not allowed at mb %d\n",img->current_mb_nr);

    mpr[jpos0][ipos0] =
    mpr[jpos1][ipos2] =
    mpr[jpos2][ipos4] =
    mpr[jpos3][ipos6] = (imgpel) ((P_Q + P_Z + 1) >> 1);
    mpr[jpos1][ipos0] =
    mpr[jpos2][ipos2] =
    mpr[jpos3][ipos4] =
    mpr[jpos4][ipos6] = (imgpel) ((P_R + P_Q + 1) >> 1);
    mpr[jpos2][ipos0] =
    mpr[jpos3][ipos2] =
    mpr[jpos4][ipos4] =
    mpr[jpos5][ipos6] = (imgpel) ((P_S + P_R + 1) >> 1);
    mpr[jpos3][ipos0] =
    mpr[jpos4][ipos2] =
    mpr[jpos5][ipos4] =
    mpr[jpos6][ipos6] = (imgpel) ((P_T + P_S + 1) >> 1);
    mpr[jpos4][ipos0] =
    mpr[jpos5][ipos2] =
    mpr[jpos6][ipos4] =
    mpr[jpos7][ipos6] = (imgpel) ((P_U + P_T + 1) >> 1);
    mpr[jpos5][ipos0] =
    mpr[jpos6][ipos2] =
    mpr[jpos7][ipos4] = (imgpel) ((P_V + P_U + 1) >> 1);
    mpr[jpos6][ipos0] =
    mpr[jpos7][ipos2] = (imgpel) ((P_W + P_V + 1) >> 1);
    mpr[jpos7][ipos0] = (imgpel) ((P_X + P_W + 1) >> 1);
    mpr[jpos0][ipos1] =
    mpr[jpos1][ipos3] =
    mpr[jpos2][ipos5] =
    mpr[jpos3][ipos7] = (imgpel) ((P_Q + P_A + 2*P_Z + 2) >> 2);
    mpr[jpos1][ipos1] =
    mpr[jpos2][ipos3] =
    mpr[jpos3][ipos5] =
    mpr[jpos4][ipos7] = (imgpel) ((P_Z + P_R + 2*P_Q + 2) >> 2);
    mpr[jpos2][ipos1] =
    mpr[jpos3][ipos3] =
    mpr[jpos4][ipos5] =
    mpr[jpos5][ipos7] = (imgpel) ((P_Q + P_S + 2*P_R + 2) >> 2);
    mpr[jpos3][ipos1] =
    mpr[jpos4][ipos3] =
    mpr[jpos5][ipos5] =
    mpr[jpos6][ipos7] = (imgpel) ((P_R + P_T + 2*P_S + 2) >> 2);
    mpr[jpos4][ipos1] =
    mpr[jpos5][ipos3] =
    mpr[jpos6][ipos5] =
    mpr[jpos7][ipos7] = (imgpel) ((P_S + P_U + 2*P_T + 2) >> 2);
    mpr[jpos5][ipos1] =
    mpr[jpos6][ipos3] =
    mpr[jpos7][ipos5] = (imgpel) ((P_T + P_V + 2*P_U + 2) >> 2);
    mpr[jpos6][ipos1] =
    mpr[jpos7][ipos3] = (imgpel) ((P_U + P_W + 2*P_V + 2) >> 2);
    mpr[jpos7][ipos1] = (imgpel) ((P_V + P_X + 2*P_W + 2) >> 2);
    mpr[jpos0][ipos2] =
    mpr[jpos1][ipos4] =
    mpr[jpos2][ipos6] = (imgpel) ((P_Z + P_B + 2*P_A + 2) >> 2);
    mpr[jpos0][ipos3] =
    mpr[jpos1][ipos5] =
    mpr[jpos2][ipos7] = (imgpel) ((P_A + P_C + 2*P_B + 2) >> 2);
    mpr[jpos0][ipos4] =
    mpr[jpos1][ipos6] = (imgpel) ((P_B + P_D + 2*P_C + 2) >> 2);
    mpr[jpos0][ipos5] =
    mpr[jpos1][ipos7] = (imgpel) ((P_C + P_E + 2*P_D + 2) >> 2);
    mpr[jpos0][ipos6] = (imgpel) ((P_D + P_F + 2*P_E + 2) >> 2);
    mpr[jpos0][ipos7] = (imgpel) ((P_E + P_G + 2*P_F + 2) >> 2);
    break;

  case  HOR_UP_PRED:/* diagonal prediction -22.5 deg to horizontal plane */
    if (!block_available_left)
      printf ("warning: Intra_8x8_Horizontal_Up prediction mode not allowed at mb %d\n",img->current_mb_nr);

    mpr[jpos0][ipos0] = (imgpel) ((P_Q + P_R + 1) >> 1);
    mpr[jpos1][ipos0] =
    mpr[jpos0][ipos2] = (imgpel) ((P_R + P_S + 1) >> 1);
    mpr[jpos2][ipos0] =
    mpr[jpos1][ipos2] =
    mpr[jpos0][ipos4] = (imgpel) ((P_S + P_T + 1) >> 1);
    mpr[jpos3][ipos0] =
    mpr[jpos2][ipos2] =
    mpr[jpos1][ipos4] =
    mpr[jpos0][ipos6] = (imgpel) ((P_T + P_U + 1) >> 1);
    mpr[jpos4][ipos0] =
    mpr[jpos3][ipos2] =
    mpr[jpos2][ipos4] =
    mpr[jpos1][ipos6] = (imgpel) ((P_U + P_V + 1) >> 1);
    mpr[jpos5][ipos0] =
    mpr[jpos4][ipos2] =
    mpr[jpos3][ipos4] =
    mpr[jpos2][ipos6] = (imgpel) ((P_V + P_W + 1) >> 1);
    mpr[jpos6][ipos0] =
    mpr[jpos5][ipos2] =
    mpr[jpos4][ipos4] =
    mpr[jpos3][ipos6] = (imgpel) ((P_W + P_X + 1) >> 1);
    mpr[jpos4][ipos6] =
    mpr[jpos4][ipos7] =
    mpr[jpos5][ipos4] =
    mpr[jpos5][ipos5] =
    mpr[jpos5][ipos6] =
    mpr[jpos5][ipos7] =
    mpr[jpos6][ipos2] =
    mpr[jpos6][ipos3] =
    mpr[jpos6][ipos4] =
    mpr[jpos6][ipos5] =
    mpr[jpos6][ipos6] =
    mpr[jpos6][ipos7] =
    mpr[jpos7][ipos0] =
    mpr[jpos7][ipos1] =
    mpr[jpos7][ipos2] =
    mpr[jpos7][ipos3] =
    mpr[jpos7][ipos4] =
    mpr[jpos7][ipos5] =
    mpr[jpos7][ipos6] =
    mpr[jpos7][ipos7] = (imgpel) P_X;
    mpr[jpos6][ipos1] =
    mpr[jpos5][ipos3] =
    mpr[jpos4][ipos5] =
    mpr[jpos3][ipos7] = (imgpel) ((P_W + 3*P_X + 2) >> 2);
    mpr[jpos5][ipos1] =
    mpr[jpos4][ipos3] =
    mpr[jpos3][ipos5] =
    mpr[jpos2][ipos7] = (imgpel) ((P_X + P_V + 2*P_W + 2) >> 2);
    mpr[jpos4][ipos1] =
    mpr[jpos3][ipos3] =
    mpr[jpos2][ipos5] =
    mpr[jpos1][ipos7] = (imgpel) ((P_W + P_U + 2*P_V + 2) >> 2);
    mpr[jpos3][ipos1] =
    mpr[jpos2][ipos3] =
    mpr[jpos1][ipos5] =
    mpr[jpos0][ipos7] = (imgpel) ((P_V + P_T + 2*P_U + 2) >> 2);
    mpr[jpos2][ipos1] =
    mpr[jpos1][ipos3] =
    mpr[jpos0][ipos5] = (imgpel) ((P_U + P_S + 2*P_T + 2) >> 2);
    mpr[jpos1][ipos1] =
    mpr[jpos0][ipos3] = (imgpel) ((P_T + P_R + 2*P_S + 2) >> 2);
    mpr[jpos0][ipos1] = (imgpel) ((P_S + P_Q + 2*P_R + 2) >> 2);
    break;

  default:
    printf("Error: illegal intra_4x4 prediction mode: %d\n",predmode);
    return SEARCH_SYNC;
    break;
  }
  return DECODING_OK;
}



/*!
 *************************************************************************************
 * \brief
 *    Prefiltering for Intra8x8 prediction
 *************************************************************************************
 */
void LowPassForIntra8x8Pred(imgpel *PredPel, int block_up_left, int block_up, int block_left)
{
  int i;
  imgpel LoopArray[25];

  memcpy(&LoopArray[0], &PredPel[0], 25 * sizeof(imgpel));

  if(block_up)
  {
    if(block_up_left)
    {
      LoopArray[1] = (((&P_Z)[0] + ((&P_Z)[1]<<1) + (&P_Z)[2] + 2)>>2);
    }
    else
      LoopArray[1] = (((&P_Z)[1] + ((&P_Z)[1]<<1) + (&P_Z)[2] + 2)>>2);


    for(i = 2; i <16; i++)
    {
      LoopArray[i] = (((&P_Z)[i-1] + ((&P_Z)[i]<<1) + (&P_Z)[i+1] + 2)>>2);
    }
    LoopArray[16] = ((P_P + (P_P<<1) + P_O + 2)>>2);
  }

  if(block_up_left)
  {

    if(block_up && block_left)
    {
      LoopArray[0] = ((P_Q + (P_Z<<1) + P_A +2)>>2);
    }
    else
    {
      if(block_up)
        LoopArray[0] = ((P_Z + (P_Z<<1) + P_A +2)>>2);
      else
        if(block_left)
          LoopArray[0] = ((P_Z + (P_Z<<1) + P_Q +2)>>2);
    }

  }

  if(block_left)
  {
    if(block_up_left)
      LoopArray[17] = ((P_Z + (P_Q<<1) + P_R + 2)>>2);
    else
      LoopArray[17] = ((P_Q + (P_Q<<1) + P_R + 2)>>2);

    for(i = 18; i <24; i++)
    {
      LoopArray[i] = (((&P_Z)[i-1] + ((&P_Z)[i]<<1) + (&P_Z)[i+1] + 2)>>2);
    }
    LoopArray[24] = ((P_W + (P_X<<1) + P_X + 2)>>2);
  }

  memcpy(&PredPel[0], &LoopArray[0], 25 * sizeof(imgpel));
}



/*!
 ***********************************************************************
 * \brief
 *    Inverse 8x8 transformation
 ***********************************************************************
 */
void itrans8x8(struct img_par *img, //!< image parameters
              int ioff,            //!< index to 4x4 block
              int joff)            //!<
{
  int i,j;
  int m6[8][8];
  Boolean lossless_qpprime = (Boolean) ((img->qp + img->bitdepth_luma_qp_scale)==0 && img->lossless_qpprime_flag==1);
  static int ipos;
  static int a[8], b[8];
  imgpel (*mpr)[16] = img->mpr[LumaComp];

  if(lossless_qpprime)
  {
    for( j = joff; j < joff + 8; j++)
    {
      for( i = ioff; i < ioff + 8; i++)
        img->m7[j][i] = iClip1(img->max_imgpel_value, (img->m7[j][i]+(long)mpr[j][i]));
    }
  }
  else
  {
    int *m7;
    for( i = 0; i < 8; i++)
    {
      m7 = &img->m7[joff + i][ioff];
      a[0] =  m7[0] + m7[4];
      a[4] =  m7[0] - m7[4];
      a[2] = (m7[2]>>1) - m7[6];
      a[6] =  m7[2] + (m7[6]>>1);

      b[0] = a[0] + a[6];
      b[2] = a[4] + a[2];
      b[4] = a[4] - a[2];
      b[6] = a[0] - a[6];

      a[1] = -m7[3] + m7[5] - m7[7] - (m7[7]>>1);
      a[3] =  m7[1] + m7[7] - m7[3] - (m7[3]>>1);
      a[5] = -m7[1] + m7[7] + m7[5] + (m7[5]>>1);
      a[7] =  m7[3] + m7[5] + m7[1] + (m7[1]>>1);

      b[1] =   a[1] + (a[7]>>2);
      b[7] = -(a[1]>>2) + a[7];
      b[3] =   a[3] + (a[5]>>2);
      b[5] =  (a[3]>>2) - a[5];

      m6[0][i] = b[0] + b[7];
      m6[1][i] = b[2] + b[5];
      m6[2][i] = b[4] + b[3];
      m6[3][i] = b[6] + b[1];
      m6[4][i] = b[6] - b[1];
      m6[5][i] = b[4] - b[3];
      m6[6][i] = b[2] - b[5];
      m6[7][i] = b[0] - b[7];
    }
    for( i = 0; i < 8; i++)
    {
      ipos = ioff + i;
      m7 = m6[i]; 
      a[0] = m7[0] + m7[4];
      a[4] = m7[0] - m7[4];
      a[2] = (m7[2]>>1) - m7[6];
      a[6] =  m7[2] + (m7[6]>>1);

      b[0] = a[0] + a[6];
      b[2] = a[4] + a[2];
      b[4] = a[4] - a[2];
      b[6] = a[0] - a[6];

      a[1] = -m7[3] + m7[5] - m7[7] - (m7[7]>>1);
      a[3] =  m7[1] + m7[7] - m7[3] - (m7[3]>>1);
      a[5] = -m7[1] + m7[7] + m7[5] + (m7[5]>>1);
      a[7] =  m7[3] + m7[5] + m7[1] + (m7[1]>>1);

      b[1] =   a[1] + (a[7]>>2);
      b[7] = -(a[1]>>2) + a[7];
      b[3] =   a[3] + (a[5]>>2);
      b[5] =  (a[3]>>2) - a[5];

      img->m7[joff + 0][ipos] = b[0] + b[7];
      img->m7[joff + 1][ipos] = b[2] + b[5];
      img->m7[joff + 2][ipos] = b[4] + b[3];
      img->m7[joff + 3][ipos] = b[6] + b[1];
      img->m7[joff + 4][ipos] = b[6] - b[1];
      img->m7[joff + 5][ipos] = b[4] - b[3];
      img->m7[joff + 6][ipos] = b[2] - b[5];
      img->m7[joff + 7][ipos] = b[0] - b[7];
    }

    for( j = joff; j < joff + 8; j++)
    {
      for( i = ioff; i < ioff + 8; i++)
        img->m7[j][i] = iClip1(img->max_imgpel_value, 
        rshift_rnd_sf((img->m7[j][i]+((long)mpr[j][i] << DQ_BITS_8)),DQ_BITS_8));
    }
  }
}